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Abstract AimWe explored the extent to which Gondwanan vicariance contributed to the circum‐Antarctic distribution of the mite harvestman family Pettalidae, a group of small, dispersal‐limited arachnids whose phylogeny has been poorly resolved, precluding rigorous biogeographic hypothesis testing. LocationContinental landmasses of former temperate Gondwana (Chile, South Africa, Sri Lanka, Australia and New Zealand). TaxonPettalidae, Opiliones. MethodsWe generated transcriptomes for a phylogeny of 16 pettalids, spanning 9 genera. Data were analysed using maximum likelihood, Bayesian inference and coalescence methods. The phylogenetic position of the Sri Lankan genusPettaluswas further explored using quartet likelihood mapping and changes in gene likelihood scores. We also estimated divergence times and looked for signatures of extinction across Antarctica and central Australia using previously published phylogenies with near‐complete species sampling constrained to match our transcriptomic results. Finally, we estimated ancestral ranges and inferred instances of vicariance. ResultsWe recovered a well‐supported topology with a division between taxa from landmasses that made up East Gondwana, and a grade of taxa from West Gondwana.Pettaluswas resolved either as the sister group of the Queensland‐endemicAustropurcellia, or as the sister group to a larger clade from East Gondwana, though favouringPettalus + Austropurcellia. Divergence times for multiple vicariance events coincided with Gondwana's breakup. Speciation–extinction analysis found one diversification process for the family: an initial burst of cladogenesis that slowed down through time. Main ConclusionsGiven that the order of cladogenesis corresponds to the order in which Gondwana fragmented, and the concurrent timing of vicariance and rifting, Gondwanan breakup explains major biogeographic patterns in Pettalidae. Some divergences predate initial rifting, but there is no evidence oftrans‐oceanic dispersal. The Sri Lanka–eastern Australia relationship makes sense in the light of large‐scale extinction across Antarctica and central Australia; however, we find no clear signatures of mass extinction. 

Mite harvesters (Arachnida: Opiliones: Cyphophthalmi) are tiny arachnids known to inhabit leaf litter on forest !oors throughout Aotearoa New Zealand, one of the world’s biodiversity hotspots. Recently, Cyphophthalmi in the genus Aoraki were discovered in caves in the northern South Island, representing the first records of cave-dwelling mite harvesters from New Zealand. A comparison of anatomical ratios taken from body and appendage measurements of the cave animals and epigean Aoraki species demonstrate that the cave animals display trends characteristic of troglobitic arthropods, suggesting adaptation to cavernicolous environments. We sequenced the mitochondrial loci COI and 16S rRNA from one of the cave specimens in order to better define the animal’s phylogenetic position and to assess the possibility that it represents a new species. Using an integrative taxonomic approach, results suggest the animals are cave-adapted populations of Aoraki westlandica. 

We review the major phylogeographic patterns in Aotearoa New Zealand’s terrestrial !ora and fauna that have been associated with the Otira Glaciation of the Pleistocene, the end of which coincides with the global Last Glacial Maximum (LGM). We focus on (1) the complexity of biogeographic histories of New Zealand species, with LGM-driven phenomena overlaying the impacts of mountain-building and other drivers of phylogeographic structure; (2) the locations of glacial refugia and sets of taxa which may have shared refugia; and (3) the role of glaciation in driving diversi"cation. We end with a brief focus on the next directions, including what can we learn about New Zealand’s glacial history by expanding our phylogeographic toolbox to include genomic methods and hypothesis-driven inference methods. We provide follow-up questions which take advantage of the wealth of phylogeographic data for New Zealand.